Java Socket - 客户端未从服务器接收

Question

当我运行程序时，它没有从服务器接收消息。它阻塞在o = in.readObject();行中。我使用（在类线程中）在类Worker中创建的输入流。

@Override
public void run() {
    System.out.println("run do worker começou.");
    try {
        //out = w.out;
        //out.flush();
        in = w.in;
        String message = null;
        Object o = null;
        boolean identifier;
        ArrayList<News> receivedNews;
        System.out.println("vai começar while true do worker.");
        while(true) {
            System.out.println("object: "+o);
            System.out.println("worker dentro do while.");
            o = in.readObject();
            System.out.println("object 2.0: "+o);
            System.out.println("worker recebeu: "+o.toString());
            if(o instanceof Boolean) {
                identifier = (Boolean) o;
                if(identifier == false) {
                    toWorker = true;
                    System.out.println("recebi o boolean");
                }
            }
            if(o instanceof String && toWorker == true) { //recebe a palavra e guarda-a como atributo
                message = (String) o;
                word = message;
                System.out.println("Worker received word: "+message);
                toWorker = false;
            }
            if(o instanceof ArrayList && toWorker == true) { //recebe as notícias
                receivedNews = (ArrayList<News>) o;
                news = receivedNews;
                System.out.println("Worker received the news");
                newsFinal = searchNews();
                w.sendListToServer(newsFinal);
                toWorker = false;
            }
        }
    } catch (IOException e) {
        e.printStackTrace();
    } catch (ClassNotFoundException e) {
        e.printStackTrace();
    }
}

服务器代码：

out.writeObject(false); // false = enviar para worker
                out.writeObject(word);
                out.writeObject(news);